Bill Clinton thinks history is repeating itself with the scrutiny of his wife's email use at the State Department, and the scandal is growing because people "wanted there to be a race" for the Democratic nomination.

"I actually am amazed that she's borne up under it as well as she has," the former president told CNN's Fareed Zakaria of wife Hillary Clinton's reaction to the attacks on her own presidential campaign. "But I have never seen so much expended on so little."

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In the interview, to be aired in full on Sunday on "Fareed Zakaria GPS," Clinton contends that there are "lots of people who wanted there to be a race for different reasons."

The only way to make that happen, he said, was to launch "a full-scale frontal assault on her, and so this email thing became the biggest story in the world."

He said he has faith that the American people will understand the issue for what it is and everything will be "all right."

However, the negative headlines are giving the former secretary of state's presidential ambitions some trouble. While she remains the frontrunner in nearly all polls that have been taken, there are also many Americans saying in those polls that they don't believe she is honest and trustworthy, and her favorability ratings have taken a hit.

Her husband, though, maintains in the interview that the email scandal shows that "we're seeing history repeat itself," and referred to the 1990s Whitewater scandal.

The media coverage has also shifted in his wife's case, said Clinton, from issues to politics by "people who want a race."

But Clinton did praise Vermont Sen. Bernie Sanders, his wife's nearest challenger for the
Democratic nomination, saying that both Hillary Clinton and Sanders "have laid out pretty detailed, positive policy positions, talking about what they would cost and, you know, you could actually have a debate there."

He panned Republican front-runner Donald Trump, saying that he believes the New York billionaire is trying to give working class, socially conservative Republicans an economic argument to believe in the party.

Bill Clinton thinks history is repeating itself with the scrutiny of his wife's email use at the State Department, and the scandal is growing because people "wanted there to be a race" for the Democratic nomination.